Careers can be defined by a Super Bowl performance—not just for players, or halftime entertainers, but also for the actors in the game’s much-anticipated commercials. Consider the case of Jesse Heiman, whose face is more familiar than his name. Nerdy and decidedly plump, he has appeared in scores of movies and TV shows as an extra.

But Heiman’s fame soared during Super Bowl XLVII, when he was featured in a GoDaddy ad making out with supermodel Bar Refaeli, supporting the company’s “where smart meets sexy” campaign. The next day Heiman logged on to Yahoo! and saw himself and Refaeli on the front page. A documentary crew began following Heiman around to see if the Super Bowl spot could propel him into the showbiz foreground. He even landed his first starring role, in a short film. “What people remember from that game,” Heiman says, “are the lights going out [in the Superdome] and me.”

Companies spend so much on Super Bowl ads chasing the same hope: that after the game, people will be talking about them. That’s why advertisers go all out, pulling stunts to grab viewers’ attention. By going for the big score, they increase the sense that the Super Bowl is a special occasion.

In the early years Super Bowl ads weren’t much different from others, though some did prove memorable. In 1974 Master Lock ran its classic spot in which a marksman pierces the body of a lock with a bullet. (Master Lock appeared in 21 Super Bowls.) Six years later Joe Greene’s “Hey kid, catch” ad for Coca-Cola appeared during Super Bowl XIV.

The modern phenomenon of the Super Bowl ad traces to 1984, when Apple aired a 60-second spot titled “1984” that was more short movie than traditional ad. It re-created the atmosphere of George Orwell’s book and only mentioned the upcoming launch of the Macintosh computer at the end, with the promise “You’ll see why 1984 won’t be like 1984.” People in the ad game viewed “1984” as a watershed. “The industry was moving to a very fast, 15-second kind of world,” says Peter Daboll, CEO of Ace Metrix, which measures the effectiveness of video advertising. “That ad was the start of the story-telling genre.”

The appeal of the long advertisement rose even as those Super Bowl seconds became ever more expensive. In 1967, a 30-second spot cost $42,000–about $300,000 in today’s dollars. For the 2016 Super Bowl, a 30-second spot will cost a record $5 million. Networks can charge advertisers so much because the Super Bowl provides an extreme version of what sports offer—a television program that is watched by a large audience at the same time.

That’s why the numbers suggest these ads can significantly bump a company’s bottom line. One study shows movies that run ads during the Super Bowl do better than ones that don’t; another shows that companies’ stock prices get at least a short-term boost from a big-game appearance. Super Bowl advertising was key to Career Builder’s overtaking Monster.com in the online job search market, says Tim Calkins, a professor of marketing at the Kellogg School of Management at Northwestern. “The Super Bowl can be a great investment,” says Calkins. “If you want to reach a large portion of the U.S. population quickly, there is nothing quite like the Super Bowl.”

It is why these ads try so hard—and sometimes too hard—to stand out. “Win the hearts and minds of America. This is what a Super Bowl ad needs to do,” says Gretchen Walsh, a senior vice president at advertising giant McKinney who has worked on several Super Bowl ads, including Budweiser’s popular talking frogs spot. She urges clients to produce a big ad for the big game that can make the many “Best” lists that appear afterward—and create a positive and lingering impression for their brand.

The success of Super Bowl ads can also be measured in the laughs it gets. Typical TV ads deploy humor about 20% of the time. For the Super Bowl it’s more than 50%, according to Ace Metrix. But humor can be risky, and those not going for yuks often opt for unassailable earnestness: Take Clint Eastwood’s “Halftime in America” pep talk to the nation on behalf of Chrysler in 2012.

Walsh says companies have become increasingly conservative in their big-game ads, perhaps, as Calkins says, because “people don’t get fired for airing an ineffective piece of advertising on Modern Family. They might well be fired for airing an ineffective ad on the Super Bowl.”

So what to make of Heiman’s GoDaddy gig? The ad can be found on many Top 10 lists, but on some worst lists too. In scoring done by Ace Metrix, Heiman’s spot ranked 45th out of the 46 that ran during the game. Daboll offered a key caveat to GoDaddy’s low ranking: the domain-name registrar became known to consumers largely through its Super Bowl advertising. “Their goal is sheer awareness,” adds Walsh. “The worst thing that happens to an ad is if no one likes it or hates it. Neutral is death.”

SUPER BOWL GOLD: 50 Years of The Big Game was published by Sports Illustrated Books, an imprint of Time Inc. Books. Copyright 2015 Time Inc. Used by permission.